Katherine is Hetty's stepmother and the second wife of Bobbie Waters. She lives in Monksby with her two children and husband. He treats her nicely but Hetty dislikes her as she is mean at first and Hetty does not believe how her father could have made such a bad choice of wife. She has two children: Mina and Ezra Waters. Mina takes after her mother and is protective of her, while Ezra is playful and is more friendly to Hetty at first.